Filamentous embolic device with expansile elements

• US 6,602,261 B2
• Filed: 05/29/2001
• Issued: 08/05/2003
• Est. Priority Date: 10/04/1999
• Status: Expired due to Term

• Current Assignee: Microvention Incorporated (Terumo Corporation)
• Original Assignee: Microvention Incorporated (Terumo Corporation)
• Inventors: Constant, Michael, Cox, Brian J., Cruise, Gregory M., Greene, George R. Jr.
• Primary Examiner(s): Robert, Eduardo C.
• Application Number:
  US09/867,340
• Publication Number:
  US 20020120276A1
• Time in Patent Office: 798 Days
• Field of Search: 606/108, 606/191, 606/194, 606/195, 606/200
• US Class Current: 606/108
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/12113 within an aneurysm
• CPC Class Codes: A61B 17/12118 for positioning in conjunction with a stent
• CPC Class Codes: A61B 17/12145 having a pre-set deployed three-dimensional shape methods of manufacturing A61B2017/00526
• CPC Class Codes: A61B 17/1215 comprising additional materials, e.g. thrombogenic, having filaments, having fibers, being coated
• CPC Class Codes: A61B 17/12154 having stretch limiting means
• CPC Class Codes: A61B 17/12163 having a string of elements connected to each other
• CPC Class Codes: A61B 17/1219 expandable in contact with liquids
• CPC Class Codes: A61B 2017/00004 (bio)absorbable, (bio)resorbable, resorptive for implantable prostheses A61F2210/0004
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61L 2430/36 for embolization or occlusion, e.g. vaso-occlusive compositions or devices artificial blood vessels A61L27/507
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: A61L 31/145 Hydrogels or hydrocolloids
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque
• CPC Class Codes: B29C 70/74 Moulding material on a relatively small portion of the preformed part, e.g. outsert moulding B29C70/845 takes precedence
• CPC Class Codes: B29L 2031/7542 Catheters

Abstract

An embolization device includes one or more expansible, hydrophilic embolizing elements non-releasably carried along the length of a filamentous carrier that is preferably made of a very thin, highly flexible filament or microcoil of nickel/titanium alloy. At least one expansile embolizing element is non-releasably attached to the carrier. A first embodiment includes a plurality of embolizing elements fixed to the carrier at spaced-apart intervals along its length. In a second embodiment, an elongate, continuous, coaxial embolizing element is non-releasably fixed to the exterior surface of the carrier, extending along a substantial portion of the length of the carrier proximally from a distal tip. In either of the embodiments, the embolizing elements may be made of a hydrophilic, macroporous, polymeric, hydrogel foam material. In the second embodiment, the elongate embolizing element is preferably made of a porous, environmentally-sensitive, expansile hydrogel that expands, after a predetermined time delay, in response to a change in an environmental parameter, such as pH or temperature.

Claims

1. A vascular embolization device, comprising:

an elongate, flexible, filamentous carrier; and

an embolizing element non-releasably fixed to the carrier, the embolizing element being formed from an expansile polymer that expands in response to a change in an environmental parameter selected from the group consisting of temperature and pH after a predetermined time interval.

2. The embolization device of claim 1, wherein the polymer is a porous hydrogel.

3. The embolization device of claim 1, wherein the embolizing element comprises an elongate, continuous, coaxial embolyzing element non-releasably fixed to the exterior surface of the carrier along a substantial portion of the length of the carrier.

4. The embolization device of claim 1, wherein the embolizing element comprises a plurality of expansile polymer fibers attached to the carrier.

5. The embolization device of claim 1, wherein the embolizing element is radiopaque.

6. The embolization device of claim 1, wherein the carrier is configured in the form of a multi-looped structure that may assume a three-dimensional shape when unconstrained.

7. The embolization device of claim 6, wherein the three-dimensional shape is selected from the group consisting of a sphere, a helix, and an ovoid.

8. A vascular embolization device, comprising:

an elongate, flexible, filamentous carrier of predetermined length; and

a plurality of expansile fibers fixed to the carrier at spaced intervals along the length of the carrier, the fibers being formed from an expansile polymer hydrogel.

9. The embolization device of claim 8, wherein the polymer hydrogel is of a type that expands in response to a change in an environmental parameter selected from the group consisting of temperature and pH after a predetermined time interval.

10. The embolization device of claim 8, wherein the carrier is configured in the form of a multi-looped structure that may assume a three-dimensional shape when unconstrained.

11. The embolization device of claim 10, wherein the three-dimensional shape is selected from the group consisting of a sphere, a helix, and an ovoid.

12. A vascular embolization device, comprising:

a flexible, filamentous carrier having an exterior surface and a distal tip; and

an expansile embolizing element non-releasably fixed coaxially to the exterior surface of the carrier at a location proximal from the distal tip, wherein the embolizing element is formed of an expansile, hydrophilic polymer that changes its physical character in response to a change in an environmental parameter selected from the group consisting of pH and temperature after a predetermined time interval.

13. The device of claim 12, wherein the carrier is formed of a flexible material having an elastic memory.

14. The device of claim 12, wherein the embolizing element is a first embolizing element fixed to the carrier at a cation, and wherein the device further comprises at least a second expansile embolizing element non-releasably fixed coaxially to the exterior surface of the carrier at a second location proximal from the distal tip.

15. The device of claim 12, wherein the carrier is configured in the form of a multi-looped structure that may assume a three-dimensional shape when unconstrained.

16. The device of claim 15, wherein the three-dimensional shape is selected from the group consisting of a sphere, a helix, and an ovoid.

17. The device of claim 12, wherein the embolizing element is formed of a strectch-resistant, biocompatible polymer.

18. The device of claim 12, wherein the embolizing element is expansible by a volumetric expansion factor of about 2×

to about 100×

.

19. The device of claim 12, wherein the polymer is a porous hydrogel.

20. A vascular embolization device that is deployable intravascularly while attached to a deployment instrument having a distal end, the embolization device comprising:

a flexible filamentous carrier having proximal and distal ends;

an embolizing element coaxially covering a substantial portion of the length of the carrier between the proximal and distal ends thereof, the embolizing element being formed of an expansile hydrophilic polymer that expands in response to a change in an environmental parameter; and

a linkage element formed of an expansile hydrogel, located on the proximal end of the carrier, that releasably attaches the embolizatlon device to the distal end of the deployment instrument.

21. A vascular embolization device that is deployable intravascularly while attached to a deployment instrument having a distal end, the embolization device comprising:

a flexible filamentous carrier having proximal and distal ends;

an embolizing element coaxially covering a substantial portion of the length of the carrier between the proximal and distal ends thereof, the embolizing element being formed of a stretch-resistant, expansile hydrophilic polymer that expands in response to a change in an environmental parameter; and

a linkage element on the proximal end of the carrier that releasably attaches the embolization device to the distal end of the deployment instrument.

22. The embolization device of claim 21, wherein the carrier comprises a material that is visible under X-rays.

23. The embolization device of claim 21, wherein the polymer is an environmentally-sensitive polymer that changes its physical character in response to a change in an environmental parameter selected from the group consisting of temperature and pH.

24. The embolization device of claim 21, wherein the embolizing element is expansible by a volumetric expansion factor of between about 2×

and about 100×

.

25. The embolization device of claim 21, wherein the embolizing element is radiopaque.

26. The embolization device of claim 21, wherein the carrier is configured in the form of a multi-looped structure that may assume a three-dimensional shape when unconstrained.

27. The embolization device of claim 26, wherein the three-dimensional shape is selected from the group consisting of a sphere, a helix, and an ovoid.

28. A vascular embolization device that is deployable intravascularly while attached to a deployment instrument having a distal end, the embolization device comprising:

a flexible filamentous carrier having proximal and distal ends;

an embolizing element coaxially covering a substantial portion of the length of the carrier between the proximal and distal ends thereof, the embolizing element being formed of an expansile hydrophilic polymer that expands In response to a change in an environmental parameter selected from the group consisting of temperature and pH; and

a linkage element on the proximal end of the carrier that releasably attaches the embolization device to the distal end of the deployment instrument.

29. The embolization device of claim 28, wherein the polymer is stretch-resistant.

30. The embolization device of claim 28, wherein the carrier comprises a material that is visible under X-rays.

31. The embolization device of claim 28, wherein the embolizing element is expansible by a volumetric expansion factor of between about 2×

and about 100×

.

32. The embolization device of claim 28, wherein the embolizing element is radiopaque.

33. The embolization device of claim 28, wherein the carrier is configured in the form of a multi-looped structure that may assume a three-dimensional shape when unconstrained.

34. The embolization device of claim 33, wherein the three-dimensional shape is selected from the group consisting of a sphere, a helix, and an ovoid.